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Detection of arterial wall abnormalities via Bayesian model selection.

ABSTRACT: Patient-specific modelling of haemodynamics in arterial networks has so far relied on parameter estimation for inexpensive or small-scale models. We describe here a Bayesian uncertainty quantification framework which makes two major advances: an efficient parallel implementation, allowing parameter estimation for more complex forward models, and a system for practical model selection, allowing evidence-based comparison between distinct physical models. We demonstrate the proposed methodology by generating simulated noisy flow velocity data from a branching arterial tree model in which a structural defect is introduced at an unknown location; our approach is shown to accurately locate the abnormality and estimate its physical properties even in the presence of significant observational and systemic error. As the method readily admits real data, it shows great potential in patient-specific parameter fitting for haemodynamical flow models.

SUBMITTER: Larson K

PROVIDER: S-EPMC6837237 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Detection of arterial wall abnormalities via Bayesian model selection.

Larson Karen K Bowman Clark C Papadimitriou Costas C Koumoutsakos Petros P Matzavinos Anastasios A

Royal Society open science 20191016 10

Patient-specific modelling of haemodynamics in arterial networks has so far relied on parameter estimation for inexpensive or small-scale models. We describe here a Bayesian uncertainty quantification framework which makes two major advances: an efficient parallel implementation, allowing parameter estimation for more complex forward models, and a system for practical model selection, allowing evidence-based comparison between distinct physical models. We demonstrate the proposed methodology by ...[more]

PMID: 31824680

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